Details

BYL-719 (Alpelisib) is a potent and selective PI3Kα inhibitor with an IC50 of 5 nM.

IC50 & Target[1]
p110α
5 nM (IC50)

In Vitro
BYL-719 (NVP-BYL719) potently inhibits the 2 most common PIK3CA somatic mutations (H1047R, E545K; IC50~4 nM). BYL-719 potently inhibits Akt phosphorylation in cells transformed with PI3Kα (IC50=74±15 nM) and shows significant reduced inhibitory activity in PI3Kβ or PI3Kδ isoforms transformed cells (≥15-fold compared with PI3Kα)[2]. BYL-719 (BYL719) decreases cell proliferation by blocking cell cycle in G0/G1 phase with no outstanding effects on apoptosis cell death in HOS and MOS-J tumor cells. BYL-719 inhibits cell migration and can thus be considered as a cytostatic drug for osteosarcoma. In murine preclinical models of osteosarcoma, BYL-719 significantly decreases tumor progression and tumor ectopic bone formation as shown by a decrease of Ki67+ cells and tumor vascularization. BYL-719 rapidly inhibits the levels of P-AKT and P-mTOR in all cell lines assessed, confirming the functional activity of BYL-719 on osteosarcoma cells. After 72 hr of treatment, BYL-719 significantly inhibits the cell growth of all osteosarcoma cell lines tested in a dose-dependent manner with an IC50 ranging from 6 to 15 µM and with the IC90 from 24 to 42 µM at 72 hr[3].

In Vivo
BYL-719 displays excellent oral bioavailability in rats, mice and dogs and does not show any significant inhibition of the CYP450 enzymes[1]. BYL-719 (BYL719) inhibits tumor growth in pre-clinical murine models of osteosarcoma. C57Bl/6J with MOS-J tumors (n=6 per group) are randomized as controls (vehicle) or BYL-719 (12.5 mg/kg or 50 mg/kg per day)[3].